1. Field of the Invention
Generally, the invention relates to lamps for flashlights. More specifically, the invention relates to such lamps which utilize a light emitting diode chip to produce light which is subsequently collimated into a beam of light for projection from the flashlight.
2. Description of the Prior Art
It is estimated that in 1998 over two hundred (200) million collimating reflector type flashlights were produced. Conventionally known flashlights which utilize a collimating reflector operate with incandescent lamps (bulbs) which have a filament placed in a geometric position compatible with the focal point of the collimating reflector.
Incandescent lamps are constructed with a xe2x80x98light center lengthxe2x80x99 or LCL which is defined as the best strait line that can be passed through the majority of the lighted coil. A collimated beam of light, defined by xe2x80x98beam candle powerxe2x80x99, is created when the coil is properly positioned to the focal point of the collimating reflector.
As a source of illumination, conventional light emitting diode chips are generally limited to small flashlights such as key chain type lights, small pen lights and small flashlights which do not utilize collimating reflectors to enhance the collimation of the produced light. This is due primarily to the narrow view angle of the produced light and the lack of utilization of light bending surfaces or other diffusion or dispersion methods. Attempts have been made to use light emitting diode chips in incandescent lamp bases. These attempts generally have been limited to providing a convenient light source for use in existing flashlights where the produced light does not interact with the collimating reflector of those flashlights. It is important to note that these replacement incandescent lamps using light emitting diode chips were not designed to operate with the collimating reflector to produce a beam of light prior to applicant""s invention.
Conventional, narrow projection angle, light emitting diode chip light sources lack light bending surfaces to broaden the narrow view angle of the produced light. The light emitting diode chip, in conventional form, does not make a satisfactory source of light for conventional flashlights because the point source of light is on a plane. The conventional light emitting diode chip is formed by the deposition of semiconductor materials and phosphors to a substrate in a planar configuration which inhibits use as a broad spectrum light source. Conventional collimating reflector flashlight require the broad spectrum light source.
The Polar light distribution of conventional light emitting diode chips is at best about one hundred and twenty-five (125) degrees and most commonly about fifteen (15) degrees. Conventional collimating reflector flashlights require a polar distribution of three hundred and sixty (360) degrees, (radially), for maximum efficiency.
Some progress has recently been made to provide for a widening of the projection angle of light emitting diode chips. A principle method of widening the projection angle of light emitting diode chips involves placement of the light emitting diode chip within a tiny cup or bowl reflector base. Work in this area has resulted in widening the projection angle from the common fifteen (15) degrees to as much as one hundred and twenty (120) degrees and slightly beyond. Typically phosphor, or another suitable material, is used as a coating over the light emitting diode chip which then acts to diffuse the light produced by the light emitting diode chip to enable the tiny reflector base to widen the projection angle. These new style light emitting diode chips are ideally suited for use with the present invention. Both the conventional light emitting diode chips and the new style coated light emitting diode chips use an acrylic or plastic molded lens.
Various methods exist in the art to alter the angle of projection of light. Such conventional methods to alter the angle of projection of light include lighted panels and annunciators, amongst others. Your applicant is unaware of utilization of such methods, prior to applicant""s invention, with light emitting diode chip light sources wherein the produced light may be efficiently used with flashlights having a conventional collimating reflector where the produced light reaches the inner wall of a collimating reflector to be collimated into a beam of light.
Light emitting diode chips which produce white light, offer a new and superior light source for collimating reflector type flashlights in that they provide superior lamp life and battery run time. Conventional light emitting diode chip light sources are unsatisfactory for direct use in flashlights with collimating reflectors due to a narrow viewing angle of the light emitting diode chip, generally between fifteen (15) degrees and thirty (30) degrees. When the conventional light emitting diode chip is positioned facing away from the collimating reflector, this narrow viewing angle projects the available light beyond the walls of the collimating reflector. When the conventional light emitting diode chip is positioned facing toward the collimating reflector, this narrow viewing angle projects the available light to only a portion of the wall of the collimating reflector. The curved collimating reflector wall therefore cannot properly act upon the produced light of conventional light emitting diode chip light sources to collimated the light beam. The new style light emitting diode chips which produce wider projection angles suffer similar deficiencies to those experienced by conventional light emitting diode chips.
For the above mentioned reasons, mere substitution of a light emitting diode chip light source for the conventional incandescent lamp in flashlights, where the flashlight has a curved collimating reflector, will fail because the substitute light emitting diode chip light source and the existing curved collimating reflector will fail to cooperate to produce an acceptable collimated beam of light.
Lamps based upon light emitting diode chips are superior to conventional lamps based upon incandescent filaments because they: 1) require less power, 2) have a longer life, 3) have a greater resistance to both shock and vibration and 4) provide generally higher color temperature.
Due to the long life of the light emitting diode chip it is conceivable that a flashlight having a light emitting diode chip as the light source would never require replacement of the light source. Due to the lower power requirement of the light emitting diode chip, batteries of such flashlights would last up to 10 times as long as batteries of conventional incandescent flashlights. This combination provides for considerable cost and environmental savings.
Efforts have been made to provide for a flashlight having a suitably narrow projection beam of light which utilize light emitting diode chips as the light source. These efforts avoid use of a collimating reflector and rely upon projection of the light from the light emitting diode chip directly onto an optical focusing lens which then projects the light passing therethrough into the narrow projection beam of light. Such flashlights, while producing an acceptable beam of light, are extremely expensive to manufacture when compared to collimating reflector type flashlights due to the expense involved with manufacture of the optical focusing lens. For this reason such flashlights are not considered applicable to the present invention.
The present invention has direct positive environmental impact by significantly reducing the number of batteries consumed by the public. As an example, conventional krypton pre-focused lamps for a collimating reflector type flashlight draws between about seven tenths (0.7) amps to two (2.0) amps. Light emitting diode chips applicable to the present invention may draws as little as about two hundredths (0.02) amps up to about seven tenths (0.7) amps while producing comparable lumens. This substantial power draw difference will result in flashlight batteries lasting substantially longer, which means less batteries required over a period of time, which means less batteries being disposed of in land fill areas.
A great need exists for a lamp for collimating reflector type flashlights where the lamp has low current draw, long life and which are inexpensive to manufacture. Numerous attempts have been made to produce collimating reflector type flashlights, and the corresponding lamps, which have the desired low current draw, long life and low manufacturing costs. These attempts have been less efficient than desired. The present invention substantially fulfills these needs. Utilization of the designs of the present invention will fill a long felt need and create a new market niche.
In view of the foregoing disadvantages inherent in the known types of lamps for flashlights, your applicant has devised a type of lamp for installation in a flashlight which will be vastly superior to current use lamps. The flashlight with which applicant""s lamps will operate will have a collimating reflector capable of having a lamp positioned thereabout where light produced by the lamp may interact with the collimating reflector to be collimated into a beam of light for projection from the flashlight. The collimating reflector will have a cavity, an aperture, a central axis, a focal point and a reflector registering plane. The aperture is positioned at a symmetrically located position at one end of the cavity. The central axis extends through a central point of the aperture and extends through the cavity such that the cavity is symmetrically positioned about the central axis. The focal point is situated within the cavity at a predetermined spacing from the reflector registering plane and on the central axis. The focal point is the position where light radiating therefrom will be collimated by the collimating reflector into the beam of light. The lamp will have a base and a light emitting diode chip emitter positioned relative to the base. The base has a center axis extending therethrough and has a lamp registering plane positioned wherein the center axis of the base perpendicularly intersects the lamp registering plane. The base is positioned relative to the aperture of the collimating reflector of the flashlight during the installation of the lamp in the flashlight with the center axis of the base aligned with the central axis of the collimating reflector following the installation. The light emitting diode emitter has a light emitting diode chip which produces light. The light emitting diode emitter also has distribution means to provide for a radial distribution of at least a portion of the light produced by the light emitting diode emitter radially outward. The distribution means producing a lighted area having an average center of radiation when the light emitting diode emitter is producing light. Placement means provides for a placement of the average center of radiation of the lighted area of the light emitting diode emitter relative to the base at a relative spacing from the lamp registering plane of the base and on the center axis of the base.
My invention resides not in any one of these features per se, but rather in the particular combinations of them herein disclosed and it is distinguished from the prior art in these particular combinations of these structures for the functions specified.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. Those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
It is therefore a primary object of the present invention to provide for a lamp, which relies upon a light emitting diode chip to produce light, for subsequent placement in a flashlight of the collimating reflector type.
Other objects include;
a) to provide for a radial distribution of light produced by the light emitting diode chip wherein the light produced by the lamp may properly interact with a collimating reflector of the flashlight into which the lamp is installed.
b) to provide for a placement of a lighted area of the lamp relative to a base of the lamp which matches a focal point of the collimating reflector of the flashlight following installation of the lamp in the flashlight.
c) to provide for properties of refraction to provide, at least in part, for the radial dispersion of the produced light.
d) to provide for properties of diffusion to provide, at least in part, for the radial dispersion of the produced light.
e) to provide for properties of reflection to provide, at least in part, for the radial dispersion of the produced light.
f) to provide for compound surface areas on a protective cover encasing the light emitting diode chip to provide for the properties of diffusion.
g) to provide for surface coatings on a protective cover encasing the light emitting diode chip to provide for the properties of reflection.
h) to provide for a scarification of an exterior surface of a protective cover encasing the light emitting diode chip to provide for the properties of diffusion.
i) to provide for a lamp having a base wherein an exterior of the base generally matches industry standard bases of conventional incandescent lamps as used for collimating reflector type flashlights.
j) to provide for the exterior of the base of the lamp to have a smooth surface generally matching industry standard smooth exterior bases of conventional incandescent lamps as used for collimating reflector type flashlights.
k) to provide for a filler material between the light emitting diode chip and a flange of the base to protect an integrity of the lamp and to maintain proper spacing of a lighted area of the lamp.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated the preferred embodiments of the invention.